Manual rotary scalpel structure

ABSTRACT

Rotary scalpel structure and method which rotary scalpel may be either manual or automatic. The manual rotary scalpel structure includes an handle having a bifurcated end between the ends of which a circular scalpel blade is mounted for rotation. The automatic rotary scalpel includes a circular scalpel blade secured at one end of a blade support arm connected to a handle having a drive motor secured to the other end thereof and means extending through the handle and the blade support arm for rotating the circular scalpel blade on energization of the motor. The automatic rotary scalpel includes structure for releasably securing the blade support arm to the handle. A circular scalpel blade is also provided which has concave surfaces to reduce blade friction along with a blade container for transporting and storing circular scalpel blades. 
     The method includes manually or automatically rotating a circular scalpel blade and drawing it across an area in which an incision is required. With the automatic rotary scalpel structure, the blade is rotated prior to the incision being made. In either case, it is desirable to rotate the rotary scalpel blade circumference at between 4 and 7 centimeters per second.

This application is a division of application Ser. No. 422,847 filedSept. 24, 1982 now U.S. Pat. No. 4,791,928.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to surgery and refers more specifically to arotary scalpel structure and method whereby an incision is made with arotating circular scalpel blade having a circumferential speedpreferably in the range of 4 to 7 centimeters per second so that scartissue at an incision is minimized.

2. Description of the Prior Art

In the past, surgical incisions have generally been made with a straightscalpel used linearly which is essentially a straight sharp knife. Withsuch structure, and particularly at the start of an incision, thematerial cut, i.e. human skin, is essentially crushed rather than cut asit would be by a moving blade as it is later during the making of theincision as the surgeon moves the blade across the area in which theincision is required. It is well known that with such scalpels and suchprocedures that in the crushed area, considerably more scar tissue willbuild up on healing of the incision than in the area where the scalpelis at the desired cutting depth and is moving along the incision planewhile the incision is being made. Scar tissue is undesirable and shouldbe minimized.

SUMMARY OF THE INVENTION

The rotary scalpel structure of the invention for practicing the methodof the invention may be either a manual rotary scalpel or a automated,that is, power driven rotary scalpel.

The manual rotary scalpel may be straight or the rotary blade may beangularly off-set from the axis of the handle of the scalpel and thefront end of the scalpel handle may be bifurcated so that the rotaryscalpel blade may be rotatably mounted between the parts of the frontend of the handle provided due to the bifurcation of the handle.

The power driven rotary scalpel includes a hollow cylindrical handle, ahousing at one end of the handle for receiving an electric motor andelectrical power for the rotary scalpel, a blade support arm at theother end of the handle on which a circular scalpel blade is mounted forrotation and means for driving the rotary scalpel blade through thesupport arm and handle from the motor including a gear box or boxes andsupport arm securing structure.

In accordance with the invention, the blade support arm is releasablysecured to the handle by rotating pin structure, which pin structure maybe bowed to reduce tolerance requirements.

The power driven rotary scalpel also includes a light for illuminatingthe area of the blade which is always on when power is applied to thepower driven rotary scalpel to indicate a power on condition.

Remote switch structure is further provided for turning on the electricmotor at the rear of the handle from the front of the handle.

The structure of the invention further includes a rotary scalpel bladehaving concave sides for reducing friction between the blade and tissueor other material being cut thereby and a hollow flat disc protector forrotary circular scalpel blades for user or maintenance protectionincluding a living hinge and an axially split resilient cylinder closuretherefore.

The method of the invention includes rotating a circular scalpel bladeand drawing it across material in which an incision is desired. In themethod of the invention, the rotary scalpel blade is rotated at a speedsuch that the circumferential speed of the rotary scalpel blade isbetween 4 and 7 centimeters per second which is the speed at whichstraight scalpels are moved in general practice.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of the power driven rotary scalpel constructed inaccordance with the invention for performing the method of theinvention.

FIG. 2 is a top view of the rotary scalpel illustrated in FIG. 1.

FIG. 3 is an enlarged, partial, longitudinal section view of the rotaryscalpel shown in FIG. 1 taken substantially on the line 3--3 in FIG. 1.

FIG. 4 is an end view of the portion of the rotary scalpel of FIG. 1shown in FIG. 3 taken in the direction of arrow 4 in FIG. 3.

FIG. 5 is a cross section of the rotary scalpel shown in FIG. 1 takensubstantially on the line 5--5 in FIG. 3.

FIG. 6 is a cross section of the rotary scalpel shown in FIG. 1 takensubstantially on the line 6--6 in FIG. 5.

FIG. 7 is an enlarged, partial longitudinal section of the rotaryscalpel shown in FIG. 1 taken substantially on the line 7--7 in FIG. 2.

FIG. 8 is a front end view of the handle of the rotary scalpel shown inFIG. 1 substantially on the line 8--8 in FIG. 7.

FIG. 9 is a front end view of the guiding and bearing member of therotary scalpel shown in FIG. 1 substantially on the line 9--9 in FIG. 7.

FIG. 10 is a back end view of the guiding and bearing member of therotary scalpel shown in FIG. 1 taken substantially on the line 10--10 inFIG. 7.

FIG. 11 is a back end view of the handle of the rotary scalpel shown inFIG. 1 taken substantially on the line 11--11 in FIG. 7.

FIG. 12 is a front end view of the motor housing of the rotary scalpelshown in FIG. 1 taken substantially on the line 12--12 in FIG. 1.

FIG. 13 is a back end view of the structure for securing the bladesupport arm to the handle of the rotary scalpel shown in FIG. 1 takensubstantially in the direction of arrow 13 in FIG. 3.

FIG. 14 is a top view of the structure illustrated in FIG. 13 taken inthe direction of arrow 14 in FIG. 13.

FIG. 15 is a side view of the structure illustrated in FIG. 13 taken inthe direction of arrow 15 in FIG. 13.

FIG. 16 is a composite figure showing three separate positions of theactuating member of the securing structure device shown in FIG. 13progressively showing the pin secured thereto in a locking position andintermediate position and an unlocking position from left to right.

FIG. 17 is a side view of a circular scalpel blade constructed inaccordance with the invention.

FIG. 18 is an enlarged section view of the scalpel blade illustrated inFIG. 17 taken substantially on the line 18--18 in FIG. 17.

FIG. 19 is an enlarged section of the free end of the blade support armand circular scalpel blade of the rotary scalpel structure illustratedin FIG. 1 taken substantially on the line 19--19 in FIG. 2 illustratingrotary mounting means for the scalpel blade illustrated in FIG. 17.

FIG. 20 is a top view of blade protector structure constructed inaccordance with the invention for the scalpel blade illustrated in FIG.17.

FIG. 21 is a cross section of the blade retainer structure illustratedin FIG. 20 taken substantially on the line 21--21 in FIG. 20.

FIG. 22 is a top view of a modified scalpel blade support arm showing acircular scalpel blade mounted in parallel with and generally along theaxis of the handle of the rotary scalpel of FIG. 1.

FIG. 23 is a top view of another modified scalpel blade support armshowing a circular scalpel blade mounted transversely of the axis of thehandle of the rotary scalpel of FIG. 1 and generally rotating on or nearthe axis of the handle.

FIGS. 24 and 25 are an elevation view taken in the direction of arrow 25and a partial top view of a manual embodiment of the rotary scalpelstructure of the invention for practicing the method of the invention.

FIGS. 26 and 27 are a partial elevation view and a partial top viewtaken in the direction of arrow 27 of a modification of the manualrotary scalpel shown in FIG. 24 showing an off-set handle.

FIG. 28 is a schematic diagram of the electrical circuit of the rotaryscalpel.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The rotary scalpel structure 10 shown in FIGS. 1 and 2 and detailed inFIGS. 3 through 19, is a power driven or automatic rotary scalpel. Therotary scalpel structure 10 as shown includes a handle 12, motor housing14 to which an electrical connector 16 is secured and which is securedto the back end 18 of the handle 12 by the coupling 20. A circularscalpel blade support arm 22 is connected to the front end 24 of thehandle 12 through the securing structure 26 and gear box 62 and supportson its outer end the circular scalpel blade 28.

Structure 30 is provided extending through the handle 12 and bladesupport arm 22 for rotating the circular scalpel blade 28 onenergization of the motor 30 in the housing 14. A light 32 is providedat the front end of the handle 24 to illuminate the scalpel blade 28.Remote switch structure 34 extends through the handle 12 to close aswitch at the back end 18 of the handle 12 to energize the motor 30.

More specifically, the handle 12 as shown in FIGS. 1 and 2 has anexterior configuration adapted to facilitate gripping of the handle by asurgeon. The handle 12 is a hollow cylindrical member substantiallyclosed at the front end having the longitudinal section configurationsshown in FIGS. 3 and 7 and the end configurations shown in FIGS. 8 and11.

The motor housing 14 as shown best in FIG. 3 is provided with a flange36 thereon which is engaged by coupling 20 secured in a threadedconnection 40 to the back end of handle 12 whereby the flange 42 on themotor 34 is held securely against the end 44 of the guiding and bearingmember 46 of the remote switch structure 24.

The switch, guiding and bearing cylinder 46 which is cylindrical andshaped as shown in longitudinal section in FIG. 3, is positioned withinthe back end 18 of the handle 12 as will be considered in more detailand subsequently.

The electrical connector 16 provides a two wire electrical connection tothe rotary scalpel structure 10. One of the incoming wires is a hot wireand may for example provide current at 4 amps from a variac at 6 voltswhile the second wire may be a grounded wire as will be consideredsubsequently in conjunction with the circuit of FIG. 27.

As shown best in FIGS. 1, 2, 3, and 19, the blade support arm 22 is ahollow tubular member, the back end 48 of which is secured at the frontend 24 of the handle 12 and on the front end 50 of which the circularscalpel blade 28 is rotatably mounted. Member 52 permits securing theblade support arm 22 to the retaining structure 54 therefore in anydesired angular position of the tubular blade support arm 22 or aboutits own axis.

Retaining structure 54 for securing the blade support arm 22 to thehandle 12 through gear box 62 as illustrated best in FIGS. 13 through 16includes a body member 56 shaped as shown to include an opening 58therein for receiving the back end 48 of the blade support arm 22. Thebody member 56 further includes the annular flange 60 to preventdisengagement of the retaining structure 54 from the gear box 62 as willbe considered subsequently and keys 62 to prevent rotation of theretaining structure 54 relative to the gear box 62.

Further, as shown best in FIG. 13, the retaining structure 54 isprovided with a pin 64 extending through a passage 66 therein which istransverse of the opening 58 and extends thereinto radially. Pin 64 isrigidly secured to a lever 68 on the retaining structure 54 whereby onrotation of the lever 68 about the axis of the pin 64, the pin 64 isrotated about its own axis in the passage 66.

Pin 64 is bowed slightly centrally along its longitudinal axis as shownin FIG. 15 to provide desired resistance to rotation about its own axiswithout additional parts and in tolerance requirements.

Rotation of the lever 68 about the axis of the pin 54 is facilitated bythe recess 70 in the lever 68 and the rounded end 72 on the lever 68.Free rotation of the lever 68 is inhibited by spring pressed detentstructure 74 and a depression 76 in the lever 68 as shown best in FIG.15.

Pin 64 has an annular groove 78 extending therearound which istransversed by a further pin 80 extending through the body member 56transversely of the pin 64 and into the annular groove 78. Thus, the pin64 is allowed to rotate with the lever 68 but is prevented from beingaxially displaced from the body member 56.

Further, as best shown in FIG. 16, the pin 64 is provided with a recess78 in one side thereof which is so shaped that on rotation of the lever68 into the position shown in FIG. 13, the recess 78 completely clearsthe opening 58 in the body member 56, that is to say, no part of the pin64 appears in the opening 58. However, with such structure, with thelever 68 rotated 180° in the direction shown by the arrows 82 the pinextends into the opening 58.

Thus, referring specifically to FIG. 5, for example, the end 48 of theblade support arm 22 may be inserted in the opening 58, with the lever68 positioned 180° from its location shown in FIG. 13 to rotate the pin64 into the position shown in FIG. 16 at the right, wherein no portionof the pin 64 extends within the opening 58. The lever 68 is thenrotated back into the position shown in FIG. 13 whereby the pin 64 isrotated into the position shown at the left in FIG. 16 through theintermediate position shown in the middle in FIG. 16 to provide aportion of the pin 64 positioned in the recess 84 in one side of the end48 of the blade support arm 22. The blade support arm 22 is thusconnected to the body member 56 of the retaining structure 54 againstdisplacement axially of the end 48 of arm 22 thereof and against angularrotation relative to the body member 56.

As shown best in FIGS. 4, 5, and 6, the retaining structure 54 is heldin place on the end 24 of the handle 12 by the gear box 62. The gear box62 is split into two separate halves 86 and 88 positioned longitudinallyof the axis of the handle 12 as shown best in FIG. 3. In assembly, theworm and worm great structure 90 as shown best in FIGS. 3 and 5, ispositioned in the gear box 62 along with the securing structure 54 andthe gear box 62 is secured to the end 24 of the handle 12 by convenientmeans such as bolts 92. The light housing 32 is constructed integrallywith the gear box 62 and supports an electric lamp 170 for illuminationof the circular scalpel blade 28 as shown best in FIG. 1.

As shown best in FIG. 19, the circular scalpel blade 28 is mounted onthe end 92 of a shaft 94 rotatably mounted in a pressed fit bearing 96which is pressed into the end 50 of the blade support arm 22. Shaft 22is connected by means of a non-circular axial opening therein 98 and asimilar non-circular end 100 secured to the end 102 of flexible drivewire 104 extending through the blade support arm 22. Thus, in operationas the flexible drive wire 104 is rotated, the shaft 94 is rotated inthe bearing 96 to rotate the circular scalpel blade 28.

Circular scalpel blade 28 is secured to the end 92 of the shaft 94 byabutment thereof against a dish shaped resilient washer 106 which urgesthe scalpel blade 28 outwardly of the shaft 94 and the resilient C-ring108 positioned within the annular recess 110 around the end 92 of theshaft 94. Relative rotation between the shaft 92 and the circularscalpel blade 28 is prevented by means of the key 112 extending intoboth the circular scalpel blade 28 and the shaft 92.

Rotation of the flexible drive wire 104 is accomplished on energizing ofthe motor 34 to rotate the motor shaft 114. Rotation of the motor shaft114 produces rotation of the shaft 116 extending through the guiding andbearing member 46 and the central bearing disc 118 assembled in thehandle 12 as shown in FIG. 3 and the passage 120 through the end 24 ofthe handle 12. A right angle worm and worm gear drive are secured to theend 122 of the shaft 116 and the shaft 124 extending perpendicularlythereto in the gear box 62. Rotation of the shaft 30 through the wormand worm gear structure 90, thus causes rotation of the shaft 124. Shaft124 again has an axially extending non-circular opening therein 126 intowhich a non-circular connector 128 of the flexible drive wire 104extends. Flexible drive wire 104 is thus rotated on rotation of theshaft 124. Accordingly, when the motor 134 is energized, the circularscalpel blade 28 is rotated.

The remote switch structure 34 as shown best in FIGS. 3,7,8 and 10includes a cylindrical shaft 130 having non-circular ends 134 and 136which extends through the length of the handle 12 and through passage140 in the bearing disc 118 passage 142 in the guiding and bearingmember 46 of the switch structure and passage 144 in the end 24 ofhandle 12. Switch structure 34 further includes the actuating member 146shaped as shown best in FIG. 8 having a non-circular opening 148therethrough and the S-shaped spring 150. At the other end of the shaft130, an electrical connector 152 is also connected by means of anon-circular opening 155 therethrough to the non-circular end 136 of theshaft 130. The end 156 of the spring 150 is rigidly secured in the end24 of the body member 12.

Thus, in operation of the remote switch structure 24, the actuatingmember 46 is normally urged counterclockwise against the stop 158 formedin the end 24 of the handle 12. On pressing of the actuating member 146it rotates about the axis of the shaft 130 with the shaft 130 againstthe bias of the spring 150 to produce rotation of the electricalconnector 152 to close the circuit switch 34 shown in FIG. 27 to providepower to the motor 34.

On release of the actuating member 146, spring 150 returns theelectrical connector 152 to its original position opening the circuit tothe motor 34.

Thus, through the structure 34, electrical switching on and off of themotor 34 may be accomplished from the front end of the handle while theactual electrical switching takes place at the back end of the handle.This satisfies requirements for manual dexterity of the surgeon andremoval of electrical switching from the material in which an incisionis required.

Referring more specifically to the electrical circuit 162, shown in FIG.28, it will be noted that the center conductor 164 is a ground linewhile conductors 166 and 168 are connected to a single hot or highvoltage input spade, the line 164 and the line 168, go directly to thelamp 170 whereby when the electrical connector 16 is attached to thecircular scalpel 10, the lamp 170 is always lit providing illuminationfrom the light structure 32. The remote switch structure 34, shownschematically in FIG. 27, then opens and closes the conductors to themotor 35 through the hot line 166 and the ground 164.

The conductors 164,166 and 168 as shown best in FIGS. 8 through 12, areessentially strap conductors which make sliding contact with each otherbetween the body member 12, the guiding and bearing member 46. Bayonetconnectors 169 are provided between the housing 14 and the guiding andbearing member 46, while electrical spade connectors 171 are providedbetween the electrical connector 16 and the housing 14. Thus, easilymanufactured positive electrical connections are provided throughout thecircular scalpel structure 10 of the invention.

Referring more specifically to FIG. 17, the circular scalpel blade 28 isa substantially flat disc having the opening 172 extending axiallythrough the middle thereof and having and outer periphery 174 sharpened.Both sides 176 and 178 of the circular scalpel blade 28 are concave asshown best in FIG. 18, whereby friction of material being cut againstthe scalpel blade 28 is materially reduced during use of the rotaryscalpel structure 10.

In operation of the circular scalpel structure 10, for best results inminimizing formation of scar tissue at the start and indeed all along anincision, it has been found that driving the rotary scalpel blade 28 ata peripheral speed of between 4 and 7 centimeters per second isparticularly desirable. Thus, the speed of the motor 34, the gearreduction in the motor and of the worm and worm gear structure 90 andthe diameter of the circular scalpel 28 have been chosen to provide sucha peripheral speed. Other peripheral speeds may of course be providedwhen considered suitable for specific surgical conditions.

The blade protector structure 200 shown in FIGS. 20 and 21, includes aflat hollow disc 202 having a stem 204, which is also hollow extendingfrom one side thereof. The disc and stem are split axially along line206 and are held together at one side by a living hinge 208 constructedof the same plastic as the disc and stem.

The circular scalpel blade 28 may thus be placed in the disc shapedrecess 210 formed in the flat disc portion 202 of the blade protectorstructure 200 with the halves of the protector separated by bending theliving hinge 208. The protector 200 is then reformed in theconfiguration shown in FIGS. 20 and 21 and a hollow cylinder 212 whichis split at 214 axially along one side thereof is positioned over thestem 204 to hold the protector in a closed position.

The cylinder 212 is constructed of resilient plastic and the internaldiameter thereof is slightly smaller than the external diameter of thestem 204 of the retainer 200.

Thus, with the structure illustrated in FIGS. 20 and 21, a circularscalpel blade may be easily transported and moved about without dangerof damaging the scalpel blade periphery or cutting someone.

The modification of the circular scalpel structure 10 illustrated inFIG. 22 includes a modified circular blade support arm 220. Similarly,the modification of FIG. 23 includes a further modified blade supportarm 222 as will be seen from a comparison of FIGS. 22 and 23. Thesupport arms 22, 220 and 222, respectively, support a circular scalpelblade 28 at an angle of 45° to the axis of the circular scalpel 10, andtranverse to the axis of the handle of the circular scalpel 10,respectively. Each of the circular scalpel blades is positioned on theaxis of the handle of the circular scalpel 10.

The different support arms 22,220, and 222 each provide a cleared areabetween the end of the handle and the scalpel blade so that the surgeonhas maximum visual access to an incision being made.

Specifically, with the support arm 22, the support arm is secured to theretaining structure 54 and extends in a circular arc for approximately135° after which it extends straight to the intersection of the supportarm and the axis of the handle of the circular scalpel 10. With thestructure of FIG. 22, the support arm extends initially in a full 180°circular arc and then straight to the axis of the handle of the circularscalpel 10. The structure of FIG. 23 is slightly different in that itfirst extends approximately 135° in a circular arc, then extends for ashort straight portion followed by a reverse curvature of 45° to theaxis of the handle of the circular scalpel 10. The initial curvature andthe reverse curvature are the same arcuate configuration in thestructure of FIG. 23.

The manual circular scalpel 228 shown in FIG. 24 includes a handle 230which is formed at 232 to aid the surgeon's grip thereon. Further, thehandle 230 is biforcated at end 234 to provide the opposed portions 236and 238 between which the circular scalpel blade 28 is secured forrotation on axle 240. As shown best in FIG. 26, the handle 230 may beprovided with an angular off-set 242 if desired to provide greatervisual access for the surgeon.

In the use of the manual scalpel structure 228, shown in FIGS. 24,25,and 26, it will be understood that the surgeon will in the best practicedraw the circular scalpel blade across the area in which the incision isdesired at a rate such that the blade 28 will rotate at thecircumference thereof at between 4 and 7 centimeters per second asindicated above to minimize scar tissue at the incision.

The blade 28 will be caused to rotate due to the frictional engagementthereof with the material being cut and again the frictional engagementbetween the blade 28 and the material being cut will be minimized due tothe concave sides 176 and 178 of the blade 28 as shown best in FIG. 18.

While different embodiments of the invention and modifications thereofhave been considered in detail, it will be understood that othermodifications and embodiments are contemplated by the inventor. Forexample, the automated rotary scalpel may be powered by a batterypositioned in the handle thereof. Also, dual, transversely spaced apartrotary blades may be provided on the same scalpel to facilitate cuttingof skin strips if desired. It is the intention to include all suchembodiments and modifications as are defined by the appended claimswithin the scope of the invention.

I claim:
 1. Completely manual rotary scalpel structure for making asurgical incision in free tissue comprising a circular scalpel blade,elongated free handle means having a longitudinal axis for holding thescalpel blade for rotation free of any other structure while moving itacross an area and along a line thereon where an incision is required ata desired incision depth and means for rotating the scalpel blade onlydue to frictional resistance of the tissue in which an incision is beingmade to passage of the circular scalpel blade therethrough, which handlemeans is bifurcated at the end adjacent the rotary scalpel blade and therotary scalpel blade is positioned centrally of the bifurcated end ofthe handle means and secured thereto for free rotation, is provided witharcuate deformation therein, the curvature of which is approximately thecurvature of the end of at least one of a human finger and a humanthumb, immediately adjacent the circular blade for facilitating grippingof the scalpel by a surgeon, is offset vertically at an oblique angle tothe longitudinal axis thereof adjacent the circular scalpel blade at anangle of approximately 60° and is offset transversely at angle ofapproximately 90° to the longitudinal axis to provide a clean field ofvision for a surgeon.
 2. Manual rotary scalpel structure for making asurgical incision comprising a circular scalpel blade and elongated freehandle means for holding the scalpel blade for rotating free of anyother structure while drawing it across an area and along a line whereinan incision is desired while the scalpel blade is rotated only due tofrictional resistance of the tissue in which an incision is being madeto the passage of the circular scalpel blade therethrough wherein thehandle means of the manual rotary scalpel has a longitudinal axis and isoffset vertically and at an oblique angle to the longitudinal axisadjacent the circular scalpel blade to provide a clean field of visionfor the surgeon.
 3. Structure as set forth in claim 2, wherein thehandle is provided with arcuate deformation therein, the curvature ofwhich is approximately the curvature of the end of at least one of ahuman finger and a human thumb, immediately adjacent the circular bladefor facilitating gripping of the scalpel by a surgeon.
 4. Structure asset forth in claim 2, wherein the end of the handle means of the manualrotary scalpel is bifurcated at the rotary scalpel blade, and the rotaryscalpel blade is positioned centrally of the bifurcated end of thehandle means and secured thereto for rotation.
 5. Structure as set forthin claim 2, wherein the handle means is offset at an angle ofapproximately 60° to the longitudinal axis thereof.
 6. Manual rotaryscalpel structure for making a surgical incision comprising a circularscalpel blade and elongated free handle means for holding the scalpelblade for rotating free of any other structure while drawing it acrossan area and along a line where an incision is desired while the scalpelblade is rotated only due to frictional resistance of the tissue inwhich an incision is being made to the passage of the circular scalpelblade therethrough wherein the handle means of the manual rotary scalpelhas a longitudinal axis and is offset transversely of the longitudinalaxis adjacent the circular scalpel blade to provide a clean field ofvision for the surgeon.
 7. Structure as set forth in claim 6, whereinthe end of the handle means of the manual rotary scalpel is bifurcatedat the rotary scalpel blade, and the rotary scalpel blade is positionedcentrally of the bifurcated end of the handle means and secured theretofor free rotation.
 8. Structure as set forth in claim 6, wherein thehandle is provided with arcuate deformation therein, the curvature ofwhich is approximately the curvature of the end of at least one of ahuman finger and a human thumb, immediately adjacent the circular bladefor facilitating gripping of the scalpel by a surgeon.
 9. Structure asset forth in claim 6, wherein the handle means is offset atapproximately 90° to the longitudinal axis thereof.